• Membrane and Water Treatment
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• v.9 no.5
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• pp.373-383
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• 2018

Fouling by solids and microorganisms is the major obstacle limiting the efficient use of membrane wastewater treatment. In our previous study, two stages microalgae/membrane filtration system was proposed to treat anaerobic digested palm oil mill effluent (AnPOME). This two stages microalgae/membrane filtration system had showed great potential for the treatment of AnPOME with high removal of COD, $NH_3-N$, $PO_4{^{3-}}$, TSS, turbidity, and colour. However, fouling behavior of the membrane in this two stages microalgae/membrane filtration system was still unknown. In this study, empirical models that describe permeate flux decline for dead-end filtration (pore blocking - complete, intermediate, and standard; and cake layer formation) presented by Hermia were used to fit the experimental results in identifying the fouling mechanism under different experimental conditions. Both centrifuged and non-centrifuged samples were taken from the medium with 3 days RT intervals, from day 0 to day 12 to study their influence on fouling mechanisms described by Hermia for ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) filtration mode. Besides, a more detailed study on the use of resistance-in-series model for deadend filtration was done to investigate the fouling mechanisms involved in membrane filtration of AnPOME collected after microalgae treatment. The results showed that fouling of UF and NF membrane was mainly caused by cake layer formation and it was also supported by the analysis for resistance-in-series model. Whereas, fouling of RO membrane was dominated by concentration polarization.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.128-128
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• 2003

The aims of this study are 1) to test oocytes and embryos collected from in-vivo and in-vitro to achieving the valuable protocol by culturing, vitrifying and thawing of oocytes/embryos, and 2) to transfer them to recipient, and finally have resulted in pregnancies from recipient females after surgical or nonsurgical transfer. In vitro maturation and fertilization were performed according to the procedures of Funahashi et al. Fertilized oocytes were cultured in glucose-free NCSU 23 supplemented with 5 mM sodium pyruvate, 0.5 mM sodium lactate and 4 mg/ml bovine serum albumin for 2 days at 39$^{\circ}C$, and 10% fetal bovine serum was added to the culture medium thereafter. Embryos were treated with 7.5$\square$g/ml cytochalasin-B for 30 min, centrifuged at 13,000 ${\times}$ g for 13 min and then exposed sequentially to an ethylene glycol (EG) vitrification solution, aspirated into OPSs, and plunged/thawed into/from liquid nitrogen. In vivo embryos were surgically collected from three donors after Al. Forty-six embryos (18, 9 and 19 embryos, respectively) were washed 3 times in mPBS+10%FBS, followed treatments : cultured, centrifuged, vitrified, recovered and transferred to recipients as in vitro prepared embryos. Three recipients received surgically 34(control), 188 and 184 embryos (derived from abattoir), respectively. Another three recipients were received nonsurgically 150, 100 and 150 embryos, respectively. All recipient sows exhibited delayed returns to estrus. To our knowledge, these results suggest that required an improved techniques, more vigorous embryos preparation and cleaner uterous condition(use gilt).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.304-310
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• 1999

This study was designed to find the effect of Minocycline loaded microcapsule applied locally to tissue by measuring drug concentration in tissue and serum by HPLC and to achieve optimal drug delivery system and duration to a specific target site. Control group were administrated minocycline intramuscularly twice a day with $0.2{\mu}g/100g$ for 1 to 10 days. In experimental group, surgical wound was created on Rt. cheek and then minocycline loaded microcapsule was applied into the space between superficial and deep layer of masseter muscle. Animals were sacrificed at 1, 3, 5, 7, 10 days after initial administration, blood was obtained from heart and right masseter muscle was excised. Blood sample was centrifuged at 3000rpm for 15min. Tissue sample was homogenized, left at room temperature for 48hr and centrifuged at 4000g for 5min. Supernatant was completely dried and dissolved in distilled water. Analysis was conducted using a ${\mu}Bondapack$ C18 column. The mobile phase was 0.2M Ammonium Oxalate/0.1M EDTA/DMF=11/4/5 solution, which was injected into the column and detected with photodiode detector at 344nm wavelength. The results were as follows : 1. This method was reliable, could be replicated and suitable for minocycline analysis in tissue as well as serum. 2. In tissue, concentration of minocycline of experimental group was higher than that of control group for 5days. 3. Except 1 day, concentration of minocycline in serum of experimental group was lower than that of control group. 4. Concentration of minocycline in tissue was much higher than that in serum. From these results, minocycline loaded microcapsule might be effective tool for local drug delivery system might be useful for treatment of infections of oral and maxillofacial region and management of infected surgical wound, minimizing systemic effects.

• Clinical and Experimental Reproductive Medicine
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• v.41 no.4
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• pp.165-167
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• 2014

Objective: The objective of this study is to estimate the effects of Inclear, a feminine cleanser, on sperm motility. Methods: Semen samples were obtained from infertile male patients. Following liquefaction, the raw semen samples were diluted with Ham's F-10 nutrient mixture medium containing 0.4% human serum albumin solution at a ratio of 1:3. The semen samples were subsequently centrifuged to separate the seminal plasma from the serum. The supernatant was discarded, and the pellet was resuspended. The sample was again centrifuged to remove cell debris, and the supernatant was removed. The final pellet was gently loosened by resuspension and incubated in medium alone as a control, and in a 10% solution of the medium plus Inclear. A sampling time of 30 minutes was selected on the basis of sperm transport studies. Sperm motility was evaluated with computer-assisted sperm analysis. Results: A total of 20 samples were analyzed. The mean age of patients was $34.40{\pm}2.96years$. There was no difference in sperm concentration and motility in the two samples at 0 minute and 30 minutes of incubation. In both semen samples, the sperm concentration and motility decreased after an incubation period of 30 minutes. However, there was no statistical difference between the samples. Sperm concentration and motility were not significantly different between the control and Inclear samples after 0 minute and 30 minutes of incubation. Conclusion: Inclear has no negative effects on sperm motility. This product can be recommended to pregnancy planners for vaginal hygiene and as a vaginal lubricant.

• Journal of Life Science
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• v.8 no.4
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• pp.400-409
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• 1998

Formation of adduct was studied in benzo(a)pyrene(BP)- and doxorubicin(Dx)-treated human NC-37 cells and isolated nuclei. Major adducts formed were determined by fluorescence absorption spectrophotometery and DNA-lin-ked protein assay. When isolated nuclei were exposed to carcinogens BP and DMBA, and anticancer drugs m-AMSA, ellipticine and Dx, varying degrees of adduct formation occured between DNA-protein complex and these drugs. When the mixture was centrifuged 1.7 M sucrose solution, binding BP and DMBA appeared to be similar between the sediment and the supernatant. When the sediment was centrifuged again with 0.35% polymin-P, the amount of BP bound was 2-fold greater in the protein(1077$\pm$55cpm) than in DNA fraction (470$\pm$20cpm), whereas that of DMBA was 1.6-fold greater in the DNA than in protein fraction. In the case of m-AMSA, ellipticine and Dx, the amount of binding was slightly greater in supernatant than in sediment in centrifugation with 1.7 M sucrose, and more than 3 times greater in the DNA- than in protein- fraction in centrifugation with 0.35% polymin P. DNA fractions which associated with a subset of nonhistone chromosomal protein were isolated from NC-37 cells exposed to $^{3}$H-BP and $^{14}$C-Dx. They were separated into two distince components DNA-S and DNA-P by centrifugation with 2M Nacl chromatin extraction. The results indicated that the amount of $^{3}$H-BP bound was 6.0-fold greater in DNA-P as compared with DNA-S, while that of $^{14}$C-Dx binding appreaed to be 6.2-fold greater in DNA-S than in DNA-P fraction. When $^{3}$H-BP binding wasdetermined in the presence of cold Dx, the amount of binding was reduced only in the DNA-P fraction, indicating that the interaction between DNA and protein is decreased. Gene expression by these drugs, BP treated cells were increased to compare with nomal cells but reduced by treatment with BP-Dx. These results suggest that the protein moiety which tightly bound to DNA-P fraction may play an important role in the regulation of gene expression.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.529-534
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• 1996

A high-performance liquid chromatographic (HPLC) assay has been developed for the determination of ketorolac in human serum using a new extraction method with a good recovery. Human serum samples (1.0 ml) spiked with known concentrations of ketorolac tromethamine and 10${\mu}g$ of ketoprofen as the internal standard (IS) were acidified with 200${\mu}l$ of 1 N HCl and extracted with 7 ml of n-hexane-ether (7:3 v/v). Extracts were centrifuged and organic layer was back-extracted with 400${\mu}l$ of 0.1% tromethamine solution. Twenty .mu.l of centrifuged aqueous layer was injected onto a reversed-phase octyl column and eluted with a mixture of acetonitrile, water, methanol, and triethylamine [35:55:10:0.1 (v/v), pH 3.0] at a flow rate of 1.0 ml/min. Ultraviolet detection of ketorolac and IS was carried out at 300 nm. The calibration curve obtained using peak area ratios showed a good linearity (in concentration range 10-150 ng/ml $r^2$=O.9944; in range 50-2000 ng/ml, r$^{2}$=0.9998). The mean intra-day accuracy and precision for this HPLC method were found to be 3.6 and 3.7%, respectively. The mean inter-day accuracy and precision were found to be 4.0 and 3.7%, respectively, in the concentration range 50-2000 ng/ml. The recovery of ketorolac from serum was 92.0 $({\pm}5.7)$ % at the concentration of 100 ng/ml. This method proved to be readily applicable to the assay of ketorolac in human serum.

• The Korean Journal of Physiology
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• v.1 no.2
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• pp.151-156
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• 1967

Outward movement of hemoglobin and $K^+$ ion across rabbit erythrocyte membrane after heating, cooling and in acid medium was studied. One milliliter of rabbit blood was centrifuged and packed red cells were obtained. Packed red cells were resuspended by addition of 4 ml of 0.9% NaCl solution and were subjected to heating $(57^{\circ}C\;for\;5\;minutes)$ or cooling $(-4^{\circ}C{\sim}-8^{\circ}C\;of\;-10^{\circ}C{\sim}-11^{\circ}C\;for\;10\;minutes) $. For acid medium experiment packed ref cells were resuspended by addition of 4 ml of acid medium of PH 4.5 consisting of 0.01% glacial acetic acid in 0.85% NaCl solution and kept standing for 10 minutes. All red cell suspensions were centrifuged again and packed red cells were separated. This packed red cells were again suspended in 4 ml of NaCl solution of 0.8%, 0.7%, 0.6%, and 0.5% concentration respectively and kept standing for 20 minutes. The concentration of hemoglobin and $K^+$ in the supernatant of the above red cell suspensions were measured and the following results were obtained. 1. Outward movement of hemoglobin and $K^+$ was greatest in red cells subjected to heating. The movement paralled to the osmolal concentration gradient between extra- and intra-cellular phase of red cells. 2. In acid medium the outflux of hemoglobin and $K^+$ increased as compared to the control. 3. In red cells subjected to the cold of $-10^{\circ}C{\sim}-11^{\circ}C$ the outflux of hemoglobin and $K^+$ increased. Whereas in the environment of $-4^{\circ}C{\sim}-8^{\circ}C$ there was no change in the outflux of $K^+$. The he-moglobin outflux showed rather a decreased as compared to tile control.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.107-114
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• 2021

This study applied with pre-treatment combined with thermal hydrolysis and seperation for disintegration of sludge. As results of particle size distribution D10, D50 and D90 of thermal hydrolyzed and centrifuged sludge was 8.6, 59.2 and 425.1 ㎛, which are lower than those of thermal hydrolyzed. The molecular weight distribution results showed that the thermal hydrolyzed sludge showed the highest proportion in the 10-100kDa range. But, Sludge, treated with combined pre-treatment, showed the highest proportion <1kDa range. Results of DOC and UVA₂₅₄ found that the organic matters of hydrolyzed sludge composed high molecular weight component above 10kDa. While, the organic matters of sludge, treated by combined pre-treatment, composed relarively low molecular weight below 1kDa. The specific methane yield of hydrolyzed and centrifuged sludge was higher 1.7 times than that of only hydrolyzed sludge.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.6
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• pp.500-505
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• 2004

The present study was to investigate the purification of a fermentation broth by an electromicrofiltration membrane. Microfiltration runs with a crude and a centrifuged broth, with solution of particles recovered from centrifugation and with permeates from microfiltration experiments were thus compared. Microfiltration performances were governed by colloids and small particles that induced sharp initial flux declines. For these results, the evolution of the overall membrane resistance was increased by $80\%$ in comparison with the electromicrofiltration membrane. The main focus of this study was set on the enhancement of the filtrate flux by an electric field. This pressure electrofiltration leads to a drastic improvement of the filtration by $100\%$ and the filtration time was thereby reduced. Pressure electrofiltration serves as an inter­esting alternative to the cross-flow filtration and it effectively separates advantageous constitu­ents such as amino acids and biopolymers from a fermentation broth. They were equally main­tained during the microelectrofiltration, although they were significantly reduced by $45\%$ by the microfiltration without the application of an electric field. Accordingly, since the electrofiltration membrane was provided more permeability, this study experimentally demonstrates that the permeability inside a membrane can be controlled using an electric field.

• Journal of Microbiology
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• v.40 no.4
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• pp.267-273
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• 2002

Urinary tract infection (UTI) is one of the most common domiciliary and nosocomial bacterial infections prevalent in both males and females. UTI is diagnosed on the basis of clinical symptoms, microscopy and culture of urine. In order to evaluate the efficacy of microscopic detection for presumptive diagnosis of UTI we analyzed urine samples of Nepalese patients. We have conducted Gram staining and counting of pus cells, red blood cells (RBC) and epithelial cells. We observed that RBC and epithelial cell counts were not sensitive enough to be used for presumptive diagnosis of UTI. However, pus cell counts as well as Gram stain are sensitive and significant enough to presume UTI. When the Gram stain result was compared with the culture result, it was statistically significant. From this, we suggest that Gram stain of centrifuged urine is a very sensitive screening method to detect bacteriuria. In addition, we found that E. coli was the most predominant microorganism causing UTI and nitrofurantoin was the most effective antibiotic against the isolated urinary pathogens.